Design and Performance Test of 2 kW Class Reverse Brayton Cryogenic System

With the increased commercialization of high-temperature superconducting (HTS) power cables cooled using liquid nitrogen and the use of liquefied natural gas as fuel, the need for large-capacity reverse Brayton cryogenic systems is gradually increasing. In this paper, the thermodynamic design of a reverse Brayton cryogenic system with a cooling capacity of the 2 kW class at 77 K using neon as a refrigerant is described. Unlike conventional reverse Brayton systems, the proposed system uses a cryogenic turbo-expander, scroll compressor, and plate-type heat exchanger. The performance test conducted on the fabricated system is also described. The isentropic efficiency of the cryogenic turbo-expander was measured to be 86%, which is higher than the design specification. The effectiveness of the heat exchanger and the flow rate and operating pressure of the refrigerant were found to be lower than the design specifications. Consequently, the refrigeration capacity of the fabricated reverse Brayton cryogenic system was measured to be 1.23 kW at 77 K. In the future, we expect to achieve the targeted refrigeration capacity through further improvements. In addition, the faster commercialization of HTS power cables and more efficient storage of liquefied natural gas will be realized.

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Methods of calculation and testing of gas equipment. Lecture № 6. Part 6. Twst methods for equipment for LNG operation

AutoGas Filling Complex + Alternative fuel ◽

10.36652/2073-8323-2020-19-10-443-466 ◽

2020 ◽

Keyword(s):

Heat Exchanger ◽

Natural Gas ◽

Test Methods ◽

Liquefied Natural Gas ◽

Test Method ◽

Operating Pressure ◽

Cryogenic Equipment ◽

Component Testing ◽

Methods Of Calculation ◽

Gas Cylinder

The results of work on the organization of a system for checking the tightness and strength of connections of components of gas-cylinder cars when using liquefied natural gas are summarized. A system for checking the tightness and conducting pressure testing of gas equipment in the conditions of the operating regulations is presented. The features of the technological process of inspection of cryogenic cylinders are summarized. Features of the test method for gas equipment components are described. The system of re-equipment of the HBA when working on LNG is considered. Test methods for LNG certification are summarized. Methods for monitoring and testing the production of LNG components are presented. Keywords liquefied natural gas; cryogenic equipment; test and operating pressure; component testing; inspection; cold and thermal crimping; cylinder insulation; LNG parameters; heat exchanger-evaporator testing

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Optimization of fin configurations and layouts in a printed circuit heat exchanger for supercritical liquefied natural gas near the pseudo-critical temperature

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2020.115131 ◽

2020 ◽

Vol 172 ◽

pp. 115131

Author(s):

Linghong Tang ◽

Lu Cui ◽

Bengt Sundén

Keyword(s):

Heat Exchanger ◽

Critical Temperature ◽

Natural Gas ◽

Liquefied Natural Gas ◽

Printed Circuit

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Design and Investigation into the Thermal and Mechanical Performance of a Polymer Composite Prototype Gas-Liquid Heat Exchanger

International Journal of Thermal and Environmental Engineering ◽

10.5383/ijtee.11.01.008 ◽

2016 ◽

Vol 11 (1) ◽

Keyword(s):

Heat Exchanger ◽

Natural Gas ◽

Polymer Composite ◽

Structural Integrity ◽

Mechanical Performance ◽

Operating Pressure ◽

Processing Application ◽

Gas Processing ◽

Natural Gas Processing ◽

Liquid Heat

Seawater-cooled metallic heat exchangers used in natural gas processing are prone to corrosion and fouling, resulting in increased operational and maintenance costs. A lab-scale polymer composite gas-liquid webbed tube bank heat exchanger is designed and evaluated for application in conditions representative of a fielded natural gas processing application. The heat exchanger thermal performance and structural integrity are investigated numerically using computational fluid dynamics (CFD) and finite element (FE) models, respectively. For polymer composite thermal conductivities above 20 W/m-K, in forced gas-side convection, the exchanger heat transfer rate is comparable to that of a high conductivity conventional metallic heat exchanger having the same geometry, at reduced materials, manufacturing and operational costs. In addition, the prototype heat exchanger would be structurally reliable at the maximum envisaged gas-side operating pressure for the application considered.

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Modeling and simulation of main cryogenic heat exchanger in a base-load liquefied natural gas plant

Computer Aided Chemical Engineering - 17th European Symposium on Computer Aided Process Engineering ◽

10.1016/s1570-7946(07)80060-5 ◽

2007 ◽

pp. 219-224 ◽

Cited By ~ 15

Author(s):

MM Faruque Hasan ◽

Iftekhar A Karimi ◽

Hassan Alfadala ◽

Henk Grootjans

Keyword(s):

Heat Exchanger ◽

Natural Gas ◽

Modeling And Simulation ◽

Liquefied Natural Gas ◽

Base Load

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Energy Savings on Automotive Air Conditioner Using Liquid-Suction Heat Exchanger Subcooler

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.554.256 ◽

2014 ◽

Vol 554 ◽

pp. 256-260 ◽

Cited By ~ 1

Author(s):

Budi Mursanto Wahyu ◽

Kasni Sumeru ◽

Abdul Aziz Azhar ◽

Nasution Henry

Keyword(s):

Heat Exchanger ◽

Numerical Analysis ◽

Vapor Phase ◽

Energy Savings ◽

Cooling Capacity ◽

Air Conditioner ◽

Condenser Temperature ◽

Refrigeration Capacity

The present study describes a numerical analysis of the effect of subcooling using liquid-suction heat exchanger (LSHX) on the performance of automotive air conditioner. Besides increasing the cooling capacity, subcooling using LSHX also generates superheating in the suction of the compressor, where the superheating ensures only vapor phase of refrigerant entering the compressor suction and reduces the risk of damage to the compressor. The results show that the refrigeration capacity improvements and COP improvements up to 11.86% and 5.64%, respectively, for the subcooling of 1 K to 10 K and the condenser temperature of 40°C to 50°C.

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Parametric Study of a Horizontal Tube Heat Exchanger for LNG Submerged Combustion Vaporiser

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.700.667 ◽

2014 ◽

Vol 700 ◽

pp. 667-677

Author(s):

Qing Li ◽

Zhi Yin Duan ◽

Qing Yu Wang ◽

Rong Liu

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Natural Gas ◽

Computer Model ◽

Parametric Study ◽

Single Phase ◽

Horizontal Tube ◽

Liquefied Natural Gas ◽

Tube Heat Exchanger ◽

Submerged Combustion

LNG (Liquefied Natural Gas) submerged combustion vaporiser is applied to convert Liquefied natural gas to gas phase natural gas through using the hot combustion gas generated from submerged combustion. This paper investigated the vaporisation and heat transfer process of a single horizontal tube, a simplified model, to simulate the heat transfer of circular tube heat exchanger used in LNG submerged combustion vaporiser. This work provides a useful computer model for the design of heat exchanger used in LNG submerged combustion vaporiser. The overall heat transfer and vaporisation process of the tube was separated into single-phase liquid, two-phase mixture and single-phase vapour heat transfer regions for calculation and analysis. Through development of a dedicated computer model, a parametric study was carried out to analyse the effects of geometrical size and operating conditions on inner surface convective heat transfer of tube. The results of study suggested that the preferable tube surface temperature for design was found between 280 K and 288 K in order to avoid frost deposition. The minimum tube length required for the overall vaporisation is predicted to be about 16 m when the inner tube diameter set between 0.24 m and 0.28 m.

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